Three way switches? Red, black and white?
I purchased a couple of the Decora Leviton three way switches – I want to replace the old switches but I am finding that with the red, white and black, there isn’t any designation on the three way switch. There is two screws on one side and one screw on the other. But where does the RED go, the Black go and the White?
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This is why sparkies make the big bucks.
3 way
The end of the switch that has 2 screws gets the travelers (the wires that alternate as conductors when switched). The end with one screw is the common (not neutral). It is to be connected to the load (light) or line, depending on which of the 2 switches you are looking at.
If you use the white wire as a hot you have to color the end to designate it as such.
Yes, I did try all of the permutations (at the bottom of the stairs). I put the white wire (ground I assume) on the side of the Leviton three way switch that has only one screw. The other (red and black), I switched back and forth on the other side with the gold screw and the black screw. It works fine, but the issue is when I go to hook up the other switch (the upstair hallway) with the same sequence, the downstair switch acts like a off on switch instead. It works to turn the light off and on, but then the upstairs switch does not work unless the downstairs switch is in the on position, if that makes sense.
There will be two screws that are identical in shape/color and one that's "distinguished" (eg, gold vs silver for the other two). And, of course, the ground screw (which may not be present at all on the old switch) which will be a different shape and green or black. (and gets the bare wire). Four screws total on a modern 3-way. The two "identical" screws are for the "traveler" wires that go to the other switch.
In a 3-way configuration (and other switch configurations) the white wire is often NOT ground. In fact, the white wire is NEVER "ground", it's neutral. The bare wire is ground.
Yes, I did try all of the permutations (at the bottom of the stairs). I put the white wire (ground I assume) on the side of the Leviton three way switch that has only one screw. The other (red and black), I switched back and forth on the other side with the gold screw and the black screw. It works fine, but the issue is when I go to hook up the other switch (the upstair hallway) with the same sequence, the downstair switch acts like a off on switch instead. It works to turn the light off and on, but then the upstairs switch does not work unless the downstairs switch is in the on position, if that makes sense.
First off, the white is supposed to be used as a neutral, and ought not be switched at all. Let's back up a bit and look at your box ....
The box ought to have wires coming into it in two places, most likely as two separate cables. In a 'perfect' world, one cable will have black, white, and bare wires, while the other cable will have black, red, white, and bare.
Now ... look at the switch. Two screws ought to look the same, while the third is different.
The different screw gets the black wire that comes from the cable with the black, white, and bare wires.
The two 'same' screws get the black and red wires from the other cable.
The white wires connect to each other, and nothing else.
The bare wires attach to a little bit of wire that connects to the green screw on the switch.
Get a book with color illustrations and a lighted tester. All depends on the kind of wiring, because there are several ways that 3 way switches can be powered. So far I haven't seen 3 way wiring that were so messed up color code wise, because a novice usually does not try 3 way wiring. First identify the power source. Usually black, and will be a 2 wire/ground cable. Disconnect this from whatever color wire and rest of wires should go dead. Once you know which is power, compare wiring against the pictures.
Power may be in the switch box or in the light fixture box.